Automotive seating arrangements generally comprise an inner core constructed from a resilient foam material and a soft trim cover. The cover is usually formed from a number of parts stitched to each other by seams along join lines. The threads of the seams are typically adapted to attach to portions of the foam core, thereby holding the cover in a fixed position with respect to the foam core.
The seam construction on automotive seating arrangements is typically carried out using either a Deck seam construction, or a French seam construction. An example of a Deck seam construction 15 is shown in FIG. 1. As shown therein, adjacent cover parts 17 and 19 are aligned along an edge 21 of each cover part, and placed with the outer surfaces of each cover part in mutual abutting contact. An overlapping margin region is thereby defined, and a first stitch line 23 applied, generally spaced from, and extending generally parallel to the aligned edge. This arrangement creates two seam flaps 25 and 27 which are then folded underneath one of the cover parts 19, and a second stitch line 29 is applied with the overlapping margin region and transverse to a top surface of the cover parts, to affix the seam flaps 25 and 27 underneath one of the cover parts 19. Thus, a two-part seam creation process is required, wherein the first stitch line 23 joins two adjacent cover parts 17 and 19, and a subsequently applied stitch line 29 adjoins the seam flaps 25 and 27 underneath one of the cover parts 19, providing a decorative finish to the seam construction.
An example of a French seam construction 30 is shown in FIG. 2. As seen therein, a French seam construction 30 is similar to the Deck seam construction 15, except that respective seam flaps 32 and 34 are folded underneath corresponding cover parts 36 and 38 (i.e., the flaps are folded in opposite directions). A first stitch line 40 is used to join the cover parts 36 and 38. Second 42 and third 44 stitch lines are subsequently applied to affix the respective seam flaps 32 and 34 to the corresponding cover parts 36 and 38. Thus, there is one join stitch line 40 and two decorative stitch lines 42 and 44 adjoining the folded over seam flaps 32 and 34 of each cover part 36 and 38 to a bottom surface of the respective cover part 36 or 38.
Both the Deck, and French seam constructions require two separate and distinct operations to complete the seam. That is, in the first operation, join stitching is applied to join the adjacent cover portions, and in a subsequent operation, a decorative stitching is applied to fix the seam flap to one, or both of the cover parts. The decorative stitching may be applied in a pattern, or with a coloured thread, which provides for a finished look to the seam construction.
There is a need in the art for an automotive seat seam construction which can be applied in a single operation, and without the need for manipulating portions of the cover parts, such as by folding or otherwise rotating the cover parts. There is a further need in the art for a seam construction which produces less waste material, as is created by the need for one or more seam flaps as need in a Deck or French seam.
In attaching the seat cover to the foam core, a fixing element is formed with, or formed to interact with, the seam construction, and thereby prevent the seat cover from shifting with respect to the foam core. One such construction and fixing element is described in U.S. Pat. No. 6,561,581 issued on May 13, 2003 to Michot et al. FIGS. 5 to 7 of Michot et al. show a hook device arranged on a tape, which is secured to the foam core at a position arranged to coincide with the seam construction of the seat cover. The hook device has a lobed end which engages the stitching of the seam construction and thus prevents relative movement between the seat cover and the foam core. In forming the stitching of the Deck seam construction, additional stitch lines are provided on the seam flap, having a loop portion which can be adapted to engage the hook device.
There is a need in the art for a simplified seam construction, which can have integrated therewith a fixing element for interaction with a foam core, or can interact with a fixing element positioned on the foam core. There is a further need in the art for a seam construction which can be applied easily and in a single operation to join adjacent cover parts and any additional elements to be integrated with the seam, such as those used for decoration, or for engaging with the foam core.